Workspace Matrix to organize virtual desktops in a grid. https://github.com/mzur/gnome-shell-wsmatrix

gTile for tiling window manager type functionality https://github.com/gTile/gTile

Vitals for quick view of system monitoring information https://github.com/corecoding/Vitals

Extension Manager via Flatpak for managing extensions https://github.com/mjakeman/extension-manager